BITURBO ENGINE DIMENSIONS

[alpa]

Then take a 2.8 18v and put there forged pistons with a target CR 8:0. With a proper mapping you'll get your 270hp at 0.6-7 bars of boost (stock it's 250hp at 0.8 bar CR 7.3:1) you'll have a very drivable car with a good torque control, and you'll reach 370hp with 3200gt turbos. These turbos make 380hp on the 3.2 v8. However going to 8000 rpm would be totally useless, the head flow capacity would be exceeded way before, probably at 5000. You might succeed to improve the heads VE but to do what, if you already had the power you wanted ?
I'm surprised you are only talking about the power, while the time is won with the torque. Power is just for max speed. If you just want 370hp at 8000 (and not a drivable, broad band torquey engine) then it requires 330nm, using a 2.8 displacement v6 turbo engine becomes overkill. A good 2.0 4 cyl turbo engine would do the job. Or you may want to run a low boost level, but then biturbo heads don't flow well enough, including the 24v. An engine is a machine, a machine has physical constraints and reasons.

 

[JK95]

That does sound like the easier way to go, needing only one engine to reach my goals. The question is how much the max rating for the turbos are, not how much they make on a stock car. Usually manifacturers don't max the turbos, so I'd hassard a guess that those turbos have the capasity of more, which I'm not allowed to be able to make. This is the reason I talk about power, not torque. My authorities don't look that much at torque, but mostly on hp, and because of that I'm left with having to go by the turbo capasity at the absolute max. The 375hp turbo I mentioned further back would probably max out at 350-360 on the crank, as 375 is the absolute max, which requires everything to be perfectly matched to it. So even if the 3200GT turbos would only make me 370hp on the crank, they are still rated for more by the turbo manifacturer, which makes them too big by my rule set.
Again, I only want the 8000 rpm for the sound, if it's completely wasted to go past 7000 and doing so only gives me trouble, heat and worse reliability, I'll just drop that. I simply like the sound of high revs, but it is no absolute demand.
For a max of 370hp I could just upgrade the internals in the 1.8 BMW 4 cyl I have and slap a turbo on it, but I want something different. My reason to go for a Maserati V6 over other engines is purely for fun, I know there are many enginesthat are more reliable, cheaper to build and easier to find parts for, but this is just a fun project for me, where the end goal is something fun to drive, that works on both tarmac and ice without ever being close to being the best at anything, and where I can take it to something like a car meet and it might surprise people by not having for example a Volvo redblock which is one of the most standard swap in Norway. So don't think I'm going for a pure race engine, or need those 8000 rpm, I'd be perfectly happy if I'm able to get 260-270hp on low boost, 350-360hp on high and never rev past 7000 rpm. I just need to be within my local rules.

 

[alpa]

Then take ghibli/qp4 2.0/2.8 turbos, they are smaller than 3200's. They should be able to make 350hp. You won't need to go past 6500. Some heavy preps on the 24v heads allow going to 8000 rpm to get 400hp from the 2.0, but you don't need this.
These v6 engines are very reliable. To me they were designed like F1 engines: light, compact, simple and robust. You just don't imagine the condition of these engines on most of the cars, and they still run. People don't change oil during years, use 15w40 semi oils, run extremely rich because idiot workshops are unable to understand and repair simple contact problems (on old cars).
You may have problems to find engine bearings, but there are solutions.
Parts are easy to find for the 2.8 18v versions. There are engines or parts on sell for acceptable prices, mainly because everybody want ghibli/qp4 2.0 24v engines (no objective reasons).

 

[alpa]

Just to add: I suggest you to buy a set of 2.0/2.5 18v conrods. They have 22mm pins instead of 25mm (not 24 as I wrote before). They are cheap on ebay. You don't need 25mm pins, and they are heavy. The rod length is the same.

 

[JK95]

Thanks again for good tips, I'll put them in my notes for when I might get to the engine part of the project.

 

[Scaf]

Here's what I'm thinking for the Westie. And as the bodywork and bonnet are just GRP, having sections refabricated to my own design/size needs, in the boat-hull-build shed here is no problem at all.

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I think this unnecessary madness should be encouraged